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CVE-2025-21640 (GCVE-0-2025-21640)

Vulnerability from cvelistv5 – Published: 2025-01-19 10:17 – Updated: 2026-08-05 11:53
VLAI
Title
sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'net' structure can be obtained from the table->data using container_of(). Note that table->data could also be used directly, as this is the only member needed from the 'net' structure, but that would increase the size of this fix, to use '*data' everywhere 'net->sctp.sctp_hmac_alg' is used.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < 5599b212d2f4466e1832a94e9932684aaa364587 (git)
Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < 03ca51faba2b017bf6c90e139434c4117d0afcdc (git)
Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < 86ddf8118123cb58a0fb8724cad6979c4069065b (git)
Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < 3cd0659deb9c03535fd61839e91d4d4d3e51ac71 (git)
Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < ad673e514b2793b8d5902f6ba6ab7e890dea23d5 (git)
Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < f0bb3935470684306e4e04793a20ac4c4b08de0b (git)
Affected: 3c68198e75111a905ac2412be12bf7b29099729b , < ea62dd1383913b5999f3d16ae99d411f41b528d4 (git)
guessed Create a notification for this product.
Linux Linux Affected: 3.8
Unaffected: 0 , < 3.8 (semver)
Unaffected: 5.4.292 , ≤ 5.4.* (semver)
Unaffected: 5.10.234 , ≤ 5.10.* (semver)
Unaffected: 5.15.177 , ≤ 5.15.* (semver)
Unaffected: 6.1.125 , ≤ 6.1.* (semver)
Unaffected: 6.6.72 , ≤ 6.6.* (semver)
Unaffected: 6.12.10 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Affected: 0 , < * (custom)
guessed Create a notification for this product.
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La estructura \u0027net\u0027 se puede obtener de table-\u0026gt;data usando Container_of(). Tenga en cuenta que table-\u0026gt;data tambi\u00e9n se puede usar directamente, ya que este es el \u00fanico miembro necesario de la estructura \u0027net\u0027, pero eso aumentar\u00eda el tama\u00f1o de esta correcci\u00f3n, para usar \u0027*data\u0027 en todos los lugares donde se use \u0027net-\u0026gt;sctp.sctp_hmac_alg\u0027.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/sctp/sysctl.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"5599b212d2f4466e1832a94e9932684aaa364587\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"03ca51faba2b017bf6c90e139434c4117d0afcdc\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"86ddf8118123cb58a0fb8724cad6979c4069065b\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"3cd0659deb9c03535fd61839e91d4d4d3e51ac71\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"ad673e514b2793b8d5902f6ba6ab7e890dea23d5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"f0bb3935470684306e4e04793a20ac4c4b08de0b\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3c68198e75111a905ac2412be12bf7b29099729b\",\"lessThan\":\"ea62dd1383913b5999f3d16ae99d411f41b528d4\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/sctp/sysctl.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3.8\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"3.8\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.4.292\",\"lessThanOrEqual\":\"5.4.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.234\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.177\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.125\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.72\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.10\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.13\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]},{\"source\":\"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e\",\"affectedData\":[{\"vendor\":\"Siemens\",\"product\":\"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem\",\"defaultStatus\":\"unknown\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"*\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H\",\"baseScore\":7.1,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.2},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-476\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"3.8\",\"versionEndExcluding\":\"6.1.125\",\"matchCriteriaId\":\"102E9A75-004D-4E72-9120-25A5A9AA7185\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.72\",\"matchCriteriaId\":\"33E12097-C88A-45B4-9677-2A961A08DD3E\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.10\",\"matchCriteriaId\":\"02D604F6-10D1-4F7B-A022-0888406A1121\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"62567B3C-6CEE-46D0-BC2E-B3717FBF7D13\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"5A073481-106D-4B15-B4C7-FB0213B8E1D4\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"DE491969-75AE-4A6B-9A58-8FC5AF98798F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"93C0660D-7FB8-4FBA-892A-B064BA71E49E\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"034C36A6-C481-41F3-AE9A-D116E5BE6895\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*\",\"matchCriteriaId\":\"8AF9DC49-2085-4FFB-A7E3-73DFAFECC7F2\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/03ca51faba2b017bf6c90e139434c4117d0afcdc\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/3cd0659deb9c03535fd61839e91d4d4d3e51ac71\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/5599b212d2f4466e1832a94e9932684aaa364587\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/86ddf8118123cb58a0fb8724cad6979c4069065b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/ad673e514b2793b8d5902f6ba6ab7e890dea23d5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/ea62dd1383913b5999f3d16ae99d411f41b528d4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/f0bb3935470684306e4e04793a20ac4c4b08de0b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"},{\"url\":\"https://cert-portal.siemens.com/productcert/html/ssa-265688.html\",\"source\":\"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-07-30T10:13:42+00:00",
      "cve": "CVE-2025-21640",
      "id": "CVE-2025-21640",
      "initial_release_date": "2025-01-19T00:00:00+00:00",
      "product_status:known_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: sctp: sysctl: cookie_hmac_alg: avoid using current-\u003ensproxy",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21640.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-30T02:06:39Z",
      "cve": "CVE-2025-21640",
      "id": "CVE-2025-21640",
      "initial_release_date": "2025-01-20T03:47:41Z",
      "product_status:known_affected": "761",
      "product_status:known_not_affected": "38",
      "product_status:recommended": "398",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-21640",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-21640.json",
      "version": "65"
    }
  }
}



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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.